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Hilly neighborhoods are associated with increased risk of weight gain among older adults in rural Japan : A 3-years follow-up study

Background: Neighborhood environments have been regularly associated with the weight status. Although the evidence is mostly limited to adults residing in western urban settings, the weight status of older adults living in rural areas is also assumed to be significantly affected by their neighborhood environments. This study aimed to identify environmental attributes specific to rural areas that c

Two-colour time-resolved spectroscopy of helium using high-order harmonics

The radiative lifetime of the ls2p1P state of helium is measured in a two-colour ionization experiment with a 5% accuracy. The state is excited by the 13th harmonic of a tunable SO ps laser and ionized by a synchronous ultraviolet laser, with a variable time delay. This experiment demonstrates that the high harmonics generated in a jet of rare gas exposed to an intense laser field provide a tunabl

High-order harmonic generation in xenon : Intensity and propagation effects

We present experimental results on high-order harmonic generation in xenon, using a Nd:YAG laser (1064 nm). The harmonic generation efficiency is studied as a function of the laser intensity in the 1013 W/cm2 range. The harmonic conversion rates show a significant change of behavior when the medium becomes ionized (∼1013 W/cm2). This effect can be understood as the change of the nonlinear response

The origin of the occurrence rate profile of gas giants inside 100 d

We investigate the origin of the period distribution of giant planets. We fit the bias-corrected distribution of gas-giant planets inside 300 d found by Santerne et al. using a planet formation model based on pebble accretion. We investigate two possible initial conditions: a linear distribution of planetary seeds, and seeds injected exclusively on the water and CO icelines. Our simulations exclud

Focused laser intensity measurement at 1018 W/cm2 and 1053 nm

We present a simple experimental setup that makes possible the measurement of the beam section at focus under full-power conditions. We demonstrate that a 1.5-TW laser system can be focused down to a 13.5-μm-diameter spot using conventional lens focalization, thus achieving laser intensities of up to 1018 W/cm2.

Third-harmonic generation in xenon in a pulsed jet and a gas cell

We report experimental studies of harmonic generation in Xe using a 1064 nm Nd-YAG laser. Third-harmonic conversion is observed in a positively dispersive medium, using a tight-focusing geometry. The intensity of third-harmonic generation in a gas cell varies much more steeply with the laser intensity than a cubic law. The reason for the breaking of the phase matching condition is discussed.

Evidence for the formation of comet 67p/churyumov-gerasimenko through gravitational collapse of a bound clump of pebbles

The processes that led to the formation of the planetary bodies in the Solar system are still not fully understood. Using the results obtained with the comprehensive suite of instruments onboard the European Space Agency's Rosetta mission, we present evidence that comet 67P/Churyumov-Gerasimenko likely formed through the gentle gravitational collapse of a bound clump of mm-sized dust aggregates ('

Ac stark shifts induced by a YAG laser in the nP and nF Rydberg series in xenon

Nonresonant ac Stark shifts of Rydberg states in Xe have been investigated by probing an atomic transition with a weak UV light in the presence of an intense YAG-laser pulse. Rydberg atoms produced through two-photon excitation, 5p → np (n = 15-48) and 5p → nf (n = 12-49), are subsequently ionized. IR-laser-induced shifts of the resonant ionization profiles are then measured. The measured shift, 3

Spectroscopy of the np and nf even-parity rydberg series in xenon by two-photon excitation

The energies of the np[1/2]o, np[3/2]2, np[5/212, nf[3/2] 2, and nf[5/2]2 Rydberg states in Xe are measured within +0.3/-0.5 cm-1 from n = 12 to n = 49. The Rydberg states are excited by nonresonant two-photon absorption and detected by dc field ionization or infrared photoionization. We determine the ionization limit and the quantum defects for the different series involved.

Fossilized condensation lines in the Solar System protoplanetary disk

The terrestrial planets and the asteroids dominant in the inner asteroid belt are water poor. However, in the protoplanetary disk the temperature should have decreased below water-condensation level well before the disk was photo-evaporated. Thus, the global water depletion of the inner Solar System is puzzling. We show that, even if the inner disk becomes cold, there cannot be direct condensation

Assessment of the genetic and clinical determinants of fracture risk : Genome wide association and mendelian randomisation study

Objectives To identify the genetic determinants of fracture risk and assess the role of 15 clinical risk factors on osteoporotic fracture risk. Design Meta-analysis of genome wide association studies (GWAS) and a two-sample mendelian randomisation approach. Setting 25 cohorts from Europe, United States, east Asia, and Australia with genome wide genotyping and fracture data. Participants A discover

Genetic sharing with cardiovascular disease risk factors and diabetes reveals novel bone mineral density loci

Bone Mineral Density (BMD) is a highly heritable trait, but genome-wide association studies have identified few genetic risk factors. Epidemiological studies suggest associations between BMD and several traits and diseases, but the nature of the suggestive comorbidity is still unknown. We used a novel genetic pleiotropy-informed conditional False Discovery Rate (FDR) method to identify single nucl

Idrottande barn och ung­domar »vaccineras« mot frakturer i vuxenlivet : Träning är bra för alla – på olika sätt

High mechanical load in alternating directions with sufficient rest in between the loading periods is one of the best stimuli to enhance bone mass and skeletal structure, both contributing independently to bone strength. The age-frame where skeletal benefits from exercise are largest is in late pre- and early peri-puberty. Recent publications with low level of evidence infer that such skeletal ben

Abnormally decreased regional bone density in athletes with medial tibial stress syndrome

Medial tibial stress syndrome, a common condition of uncertain origin found in athletes, is characterized by pain in the distal posteromedial aspect of the tibia during exercise, with or without increased scintigraphic uptake in the affected region. To determine whether medial tibial stress syndrome with increased scintigraphic uptake is associated with a change in tibial bone mineral density conf

Independent validation of metric optimized gating for fetal cardiovascular phase-contrast flow imaging

PURPOSE: To validate metric optimized gating phase-contrast MR (MOG PC-MR) flow measurements for a range of fetal flow velocities in phantom experiments. 2) To investigate intra- and interobserver variability for fetal flow measurements at an imaging center other than the original site.METHODS: MOG PC-MR was compared to timer/beaker measurements in a pulsatile flow phantom using a heart rate (∼145

Location of myocardium at risk in comparison between single photon emission computed tomography, magnetic esonance imaging and electrocardiography

The aim of the present study was to test the hypothesis that perfusion SPECT, estimation of regional wall thickening using MRI and the distribution of ST changes on the admission ECG display similar localization of the MaR in patients with reperfused first-time MI. Eleven patients with first-time MI with ST-elevation underwent percutaneous coronary intervention (PCI), SPECT imaging within 3 hours